Forget horror movies. Some of the scariest moments we've ever seen have happened on television, within the short span of a half-hour or one-hour TV episode. We've painstakingly compiled the 50 scariest episodes of science fiction and fantasy television, and here are numbers 26-50.

To compile this list, we spent hours debating amongst ourselves and searching our DVD collections. And then, once we had a longlist of 100 or 120 episodes, we went and asked on the io9 Facebook page, just to make sure we weren't missing anything. (Thanks to everyone who responded!) And we tried to avoid having more than two or three episodes of any one show. So here's what we ended up with. Come back next week to see the top 25!

50) Trilogy of Terror, “Amelia”

What it's about: Basically, this was a TV movie anthology, compiling three different stories by Richard Matheson. Matheson actually wrote the script for "Amelia," in which Karen Black finds a Zuni fetish doll that comes to life and torments her.

49) Eerie, Indiana, “Just Say No To Fun”

What it's about: In this kids' series, Marshall discovers that the school nurse is turning his fellow kids into zombies who are incapable of having fun.

Why it's scary: It's the spooky glasses, and the hypno-eye exam, and the general sense of repression and mind control, that make this a particularly nasty episode.

48) Goosebumps “Welcome to Dead House”

What it's about: The 1990s TV adaptations of the R.L. Stine books reached their most intense level, with this adaptation of the first book in which a family moves into a house full of zombies, who want to zombify them.

47) Friday The 13th: The Series, “The Inheritance”

What it's about: Like a number of episodes on this list, it's an episode about a creepy doll — a talking doll, in fact, which loves murder and encourages people to lose their inhibitions. When Vida the doll falls into the hands of Mary (Sarah Polley) Mary's stepmom is doomed.

Why it's scary: There's just something awful about a porcelain doll murdering people. And the little kid being led into evil is always a horrifying sight.

46) Kolchak: The Night Stalker, “The Zombie”

What it's about: An old Haitian woman is using voodoo to resurrect a dead man, so he can take revenge on all the Chicago mobsters who killed him.

Why it's scary: According to this IMDB review, it's the way the zombie appears out of nowhere, lifts his victims and breaks their spines with an audible "Snap!" — before vanishing into the night again.

45) The Evil Touch, “The Trial”

What it's about: This Australian horror anthology series was known for its twist endings and insane storylines, and in this episode, a stuck-up tycoon gets trapped at a carnival and chased by a surgeon who's determined to give him a lobotomy.

44) Angel, “I’ve Got You Under My Skin”

What it's about: After one of Cordelia's visions shows a family in trouble, Angel and Wesley are forced to perform an exorcism on a young boy possessed by a demon.

Why it's scary: The exorcism itself is terrifying and intense — but the truly terrifying scenes occur afterwards, when we realize that the demon wanted to be saved from the monstrous little boy it was trapped in. And the unpossessed boy tries to burn his family alive.

43) Game of Thrones "The Pointy End"

Why it's scary: Game of Thrones has plenty of scary moments, but this is the episode where everything starts to fall apart for all the heroes. But it's really Jon's first encounter with the wight that makes the episode memorable — one single zombie brings with it as much fear as an entire horde does in shows like The Walking Dead.

42) Buffy the Vampire Slayer, “Conversations With Dead People”

What it's about: The First Evil appears separately to Willow and Dawn while Buffy deals with a former classmate who has become a vampire.

Why it's scary: This is a good example of psychological, rather than physical, horror. The real dread here is of confronting your dead loved ones and having to deal with the pain and misery of loss. That's what makes this one of the scariest episodes of Buffy.

41) Millennium, “Pilot”

What it's about: The creepy show from The X-Files' Chris Carter hits the ground running, with an intense episode that starts with a man hallucinating a stripper covered in blood (who then dies), and ends with Frank Black getting disturbing photos of his family in the mail.

Why it's scary: The killer's weird hallucinations go to the heart of our fear of serial killers, as we see through his eyes. And the tormented Frank Black is walking on the edge, in a way that's fascinating and intense to watch.

40) True Blood, “I Don’t Wanna Know”

What it's about: This horror packed episode of True Blood shows Sookie discovering that Sam is a shapeshifter, Bill being forced to turn a young woman into a vampire, and Jason continuing to keep a vampire chained up in his basement.

Why it's scary: The really scary stuff happens when Tara goes to a voodoo woman for an exorcism and is forced to kill a demon version of herself as a child. Seeing her stab herself — and finding out later that it didn’t work — is terrifying and heartbreaking.

39) The Ray Bradbury Theater, “Playground”

What it's about: There's a reason Ray Bradbury was featured in Guillermo del Toro's recent horror-themed Simpsons "couch gag" — he was capable of some terrifying storytelling. In this episode of his anthology series, William Shatner is dealing with his past bullying, only to get trapped in the body of a child and bullied all over again.

Why it's scary: It's the perfect metaphor for the way that childhood bullying can follow you around for the rest of your life — but it's also our greatest fear, being dragged back into the hell we escaped from.

38) Night Gallery, "The Caterpillar"

What it's about: Remember that scene in Wrath of Khan where a bug crawls in Chekov's ear and gets at his brain? This Rod Serling show probably helped inspire that. Macy conspires to put a brain-eating earwig into the ear of an old man whose wife he covets — but instead, it's Macy who gets the earwig on his brain.

37) Adventure Time, "The Creeps"

What it's about: It's a party! Except that a ghost seems to killing the guests one by one. Except that it's actually Jake playing a prank on Finn. Except that... the ghost is real?

Why it's scary: Adventure Time already has plenty of messed up stuff happen on a regular basis, but this episode is special. Characters drop dead left and right the whole episode (often by melting or dismemberment), which is pretty scary when you don't know it's all a prank by Jake. But what's actually scary is when a giant, freaky, green-haired ghost appears to Finn and a room in the house tries to eat him... and we don't get an explanation for two years.

36) The Outer Limits “Demon With a Glass Hand”

What it's about: Harlan Ellison turns in a bizarre tale of a man with a computer for a hand, who discovers that he's actually a robot from the future, tasked with preserving the human race from an alien invasion.

Why it's scary: In true Twilight Zone fashion, the scares don't just come from the terrifying creatures or the final reveal that Trent is a robot — but rather from the existential dread of spending 1,200 years alone waiting to save the human race.

35) Hammer House of Horror “The House that Bled to Death”

What it's about: Another horror anthology series, this time from the great British Hammer Studios. This time around, they serve up a classic haunted house story, with a decent amount of gore and a twist ending.

34) American Horror Story, “Halloween”

What it's about: The massive two-parter reveals all the horrors behind the house of monsters. The secret behind Chad and Patrick's falling out and sudden death is exposed. The murdered mistress, Hayden, pulls herself out of the grave. Addie is killed and Constance loses her marbles trying to drag her dying daughter into the safe spirit zone of their house. And finally Tate's big, terrible secret is revealed by the cast of the undead Breakfast club.

Why it's scary: This Halloween special was a doozy just on content alone. Everything is terrifying and bloody and gross and it just makes you want to hide away forever.

33) The Simpsons, “Treehouse of Horror VI”

What it's about: This sixth installment of The Simpsons' yearly Treehouse of Horror series aired in 1995 and featured an attack by living advertisements, a parody of Nightmare on Elm Street, and Homer trapped in 3D world.

Why it's scary: While still funny, this Treehouse gives us indelible images: a world where billboards and giant "Lard Lad" statues come to life and rip apart the town, Groundskeeper Willie as Freddy Krueger, and the truly horrifying idea of Homer in our world.

32) The Alfred Hitchcock Hour, “The Monkey’s Paw”

What it's about: It's the classic "be careful what you wish for" story, in which the three wishes have horrible consequences.

Why it's scary: True to Hitchcock form, the scares come as much from the characters struggling against their doom as from the creepy twists.

31) Supernatural, “No Rest For the Wicked”

What it's about: The demon Lilith possesses a little girl and terrorizes her innocent family while Dean prepares to die and go to hell.

Why it's scary: Demon children are always creepy, but Lilith takes it to a new level as she bounces from angry murder to cheerfully acting like a real child.

30) Garfield’s Halloween Adventure

What it's about: Yes, really. A Garfield TV special. Because this story of Garfield and Odie getting marooned on a boat, finding a deserted old house, and encountering ghosts who've come back for their treasure is legendarily bone-rattling.

Why it's scary: All the little touches, like the clown TV announcer, the weird old man who knows about the ghosts... and the way the old man is suddenly on Garfield's television when he gets home. This is a show that knows kids are scared that television might be watching them back.

29) The X-Files, “Tooms”

What it's about: A sequel to the first-season episode "Squeeze," where the FBI tracked Eugene Tooms, a nearly immortal serial killer who can stretch himself through small spaces to kill and eat his victim's livers. "Tooms" has the killer released from a sanitorium, with only Mulder convinced that he'll kill again.

Why it's scary: The episode's a slow burn, but it points out that these creatures Mulder and Scully capture can't really go to conventional prison, since his (true) belief that he's an immortal who needs to eat livers before entering a 30 year hibernation is going to net him an insanity plea — which means Tooms is bound to get out. You keep waiting to see when Tooms will lose it and have to feed — and the tension lasts right up until he finally snaps, and his bile-covered chase of Mulder is honestly scary.

28) The Twilight Zone 1980s, “Gramma”

What it's about: Stephen King and Harlan Ellison wrote the script for this episode. (And this is when George R.R. Martin was a producer and story consultant on the show as well.) This episode is based on King's own short story about a boy who's taking care of his senile grandmother... when she starts acting kind of monstrous.

Why it's scary: The red-eyed old lady and her moments of beastly weirdness are terrifying enough — but sort of like "Playground," this also plays on our fears about being sucked into familiar horror, as the young boy is symbolically devoured by his grandmother.

27) Star Trek: The Next Generation, “Night Terrors”

What it's about: After discovering that the abandoned USS Brattain is full of corpses, the crew stops having dreams and strange things begin happening on the Enterprise.

Why it's scary: The eerie music and terrifying hallucinations the crew experience makes this one of Star Trek’s creepiest episodes. Doctor Crusher’s hallucination of a room full of cadavers suddenly sitting up remains one of the scariest scenes ever on television.

26) Thriller, “Pigeons From Hell”

What it's about:Boris Karloff hosts this horror anthology show, and this episode is based on a spine-tingling Weird Tales story by Robert E. Howard, about two brothers who get stranded in the middle of nowhere at an abandoned house... which turns out not to be as empty as they'd thought.

Why it's scary: Stephen King himself praised this episode as one of the scariest ever, and it's full of touches like a snake jumping out of a fireplace to bite the main character, and moving shadows that make the house look like it could be full of snakes. Eeep... snakes...